The GYP project wasn't correctly depending on the various layer
targets, like the GN was.

BUG=angleproject:1319

Change-Id: I54794c71be899fe5ba40cb999ecf2ce7c4a972b5
Reviewed-on: https://chromium-review.googlesource.com/425941Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>